diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 78 |
1 files changed, 73 insertions, 5 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3b67144dead2..cf7ca7e70777 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -36,6 +36,7 @@ static struct kset *iommu_group_kset; static DEFINE_IDA(iommu_group_ida); +static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; struct iommu_callback_data { const struct iommu_ops *ops; @@ -112,6 +113,18 @@ static int __iommu_attach_group(struct iommu_domain *domain, static void __iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group); +static int __init iommu_set_def_domain_type(char *str) +{ + bool pt; + + if (!str || strtobool(str, &pt)) + return -EINVAL; + + iommu_def_domain_type = pt ? IOMMU_DOMAIN_IDENTITY : IOMMU_DOMAIN_DMA; + return 0; +} +early_param("iommu.passthrough", iommu_set_def_domain_type); + static ssize_t iommu_group_attr_show(struct kobject *kobj, struct attribute *__attr, char *buf) { @@ -1015,10 +1028,19 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev) * IOMMU driver. */ if (!group->default_domain) { - group->default_domain = __iommu_domain_alloc(dev->bus, - IOMMU_DOMAIN_DMA); + struct iommu_domain *dom; + + dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type); + if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) { + dev_warn(dev, + "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA", + iommu_def_domain_type); + dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA); + } + + group->default_domain = dom; if (!group->domain) - group->domain = group->default_domain; + group->domain = dom; } ret = iommu_group_add_device(group, dev); @@ -1083,8 +1105,12 @@ static int iommu_bus_notifier(struct notifier_block *nb, * result in ADD/DEL notifiers to group->notifier */ if (action == BUS_NOTIFY_ADD_DEVICE) { - if (ops->add_device) - return ops->add_device(dev); + if (ops->add_device) { + int ret; + + ret = ops->add_device(dev); + return (ret) ? NOTIFY_DONE : NOTIFY_OK; + } } else if (action == BUS_NOTIFY_REMOVED_DEVICE) { if (ops->remove_device && dev->iommu_group) { ops->remove_device(dev); @@ -1652,6 +1678,48 @@ void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr) } EXPORT_SYMBOL_GPL(iommu_domain_window_disable); +/** + * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework + * @domain: the iommu domain where the fault has happened + * @dev: the device where the fault has happened + * @iova: the faulting address + * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...) + * + * This function should be called by the low-level IOMMU implementations + * whenever IOMMU faults happen, to allow high-level users, that are + * interested in such events, to know about them. + * + * This event may be useful for several possible use cases: + * - mere logging of the event + * - dynamic TLB/PTE loading + * - if restarting of the faulting device is required + * + * Returns 0 on success and an appropriate error code otherwise (if dynamic + * PTE/TLB loading will one day be supported, implementations will be able + * to tell whether it succeeded or not according to this return value). + * + * Specifically, -ENOSYS is returned if a fault handler isn't installed + * (though fault handlers can also return -ENOSYS, in case they want to + * elicit the default behavior of the IOMMU drivers). + */ +int report_iommu_fault(struct iommu_domain *domain, struct device *dev, + unsigned long iova, int flags) +{ + int ret = -ENOSYS; + + /* + * if upper layers showed interest and installed a fault handler, + * invoke it. + */ + if (domain->handler) + ret = domain->handler(domain, dev, iova, flags, + domain->handler_token); + + trace_io_page_fault(dev, iova, flags); + return ret; +} +EXPORT_SYMBOL_GPL(report_iommu_fault); + static int __init iommu_init(void) { iommu_group_kset = kset_create_and_add("iommu_groups", |